SYDNEY HARBOUR BRIDGE MAP

More than 3 million people have climbed to the top of the bridge since 1998.

One of Australia’s most recognizable landmarks and arguably the world’s most dramatically situated crossing is the Sydney Harbour Bridge, whose distinctive arched profile earned it the local nickname “the coat hanger.” Synonymous with Sydney, the talismanic structure can be seen from every spot in the city.

Originally, it was not planned as an arch. John J. C. Bradfield (1867-1943), chief engineer of the New South Wales Department of Public Works, had fielded numerous cantilever and arch bridge proposals and had prepared one of his own. But after seeing Gustav Lindenthal’s powerful Hell Gate Bridge in New York (see here), he scrapped them, implementing a two-hinged arch design by Sir Ralph Freeman (1880-1950) of the British firm Dorman Long. There is some question about who originated the design; it appears that Freeman modified Bradfield’s design. From a distance it has a kind of gallant restraint, majestic but not assertive, but up close it is all might. It soars above you, so high that you could pass a ten-story building beneath it, and looks like the heaviest thing on earth.

Arch bridges ordinarily require falseworkelaborate scaffolding that supports the arch during construction. Because the new bridge was to be built over the deepest part of the harbor, the use of such temporary supports was impractical. Instead, the two halves of the arch were cantilevered out from each bank until they could be joined at midspan. Steel cables suspended from the arch support the deck, which carries four rail and tram tracks, eight traffic lanes, and pedestrian walkways.

SYDNEY HARBOUR BRIDGE MAP Photo Gallery

The Sydney bridge is flanked by a pair of ornamental Egyptoid pylons, which, until 1990, when they were adapted as ventilators for a new underground tunnel, had no functional purpose other than to provide visual reassurance of the bridge’s stability. It differs from its near twin, the Hell Gate, in one important respect: the arch’s upper chord terminates just before the pylons, clarifying the true structural role of the arch’s lower chord, which springs from the abutments; at Hell Gate the upper chord is buried in the masonry piers.

The Bayonne Bridge between New Jersey and New York, another immense though far lighter steel arch, designed by Othmar Ammann, opened shortly before the Sydney bridge. Less than 2 feet (.5 meters) longer, the Bayonne arch dashed Sydney’s claim to the title of the world’s longest steel arch. The Sydney Harbour Bridge does, however, boast a deck 160 feet (49 meters) widethe world’s broadest until surpassed in 2012 by the Port Mann Bridge in Vancouver; with a 259-foot (79-meter)-wide deck, the San Francisco-Oakland Bay Bridge East Span (2013) currently holds the record for width.

BridgeClimb, started in 1998, lets visitors and Sydneysiders take in breathtaking views from the top of the arch, 440 feet (134 meters) above the harbor, after scaling a series of catwalks, ladders, and stairs.

Nonetheless, the Australian Worker praised the Sydney Harbour Bridge upon its completion, deeming it a symbol “of what shall yet become universal.” Almost overnight, the bridge was the focus of stories, photographs, paintings, and postcards, and miniaturized as souvenirs. Suddenly the world knew Sydney, and Sydney, momentarily possessing the world’s widest if not its longest bridge, began to conceive of itself on a global scale.

The city’s geography is defined by the bridge. Northern Sydney is north of the bridge, southern Sydney is south. Western Sydney starts immediately west of the bridge, and the eastern suburbs lie to its east.

A Bailey bridge-turned-ramp descends into Ground Zero in Manhattan, enabling personnel, equipment, and materials to enter the site, devastated on September 11, 2001. U.S. paratroopers cross the Euphrates River on a temporary pontoon bridge erected in 2009.

U.S. Marines building a pontoon bridge in 1923.

Eight soldiers and a single launch vehicle can erect a DSB across a 151-foot (46-meter) gap in less than 90 minutes. This Dry Support Bridge (DSB) was manufactured by WFEL, a leading supplier of tactical military bridges, and launched in Switzerland following severe flooding.